perfhooks

Perfhooks is a built-in module in Node.js that provides an API for measuring performance metrics. It is designed to help developers monitor and optimize the performance of their applications. The module includes several key components:

The PerformanceObserver class allows developers to observe performance metrics such as timing, resource loading, and garbage collection. By creating an instance of PerformanceObserver and subscribing to specific performance entry types, developers can receive notifications when new performance entries are recorded.

The performance object is a global instance of the Performance class, which provides methods for measuring time durations, recording performance marks, and retrieving performance entries. Developers can use the performance.mark() method to create a timestamped mark, and the performance.measure() method to calculate the duration between two marks.

The performance.timing object provides detailed timing information about the loading and execution of a web page. This includes metrics such as navigationStart, fetchStart, domContentLoadedEventEnd, and loadEventEnd, which can be used to analyze the performance of a web application.

The performance.now() method returns a high-resolution timestamp, which can be used to measure the duration of operations with high precision. This is particularly useful for performance profiling and optimization.

Perfhooks is a powerful tool for developers looking to optimize the performance of their Node.js applications. By providing a comprehensive set of performance measurement and monitoring tools, it enables developers to identify bottlenecks, optimize code, and improve the overall user experience.